title: Acetylsalicylic acid-induced biochemical changes in gastric juice: a failure of adaptation?
abstract: BACKGROUND
  Acetylsalicyclic acid (ASA) causes gastric mucosal damage which diminishes with continued use due to adaptation.
  
  
  METHODS
  To determine the net effect of these processes on the gastric juice, we estimated acid, osmolality, bicarbonate concentration in nonparietal gastric juice, calcium, potassium and sodium in 18 patients (9 men; mean age 32 years, range 20-46) with irritable bowel syndrome, before and after 600 mg of ASA taken post-cibum thrice daily for 4 weeks. Osmolality was determined by an osmometer, acidity by titration, and Na+, K+ and Ca++ using a sodium-potassium-calcium analyzer; bicarbonate was derived from the two-component model of Feldman.
  
  
  RESULTS
  Gastric juice K+ and Na+ increased significantly from mean (SE) 14.6 (0.5) and 197.5 (16.3) to 16.7 (0.4) and 256.8 (18.1) mEq/L, respectively. The other parameters remained unchanged.
  
  
  CONCLUSIONS
  After four weeks of ASA ingestion there is a dichotomy of gastric mucosal injury and adaptation, with preservation of acid secretion but continued loss of Na+ and K+.
authors.affiliation: Department of Gastroenterology, Postgraduate Institute of Medical Education and Research, Chandigarh.
authors.forename: C K
authors.initials: CK
authors.lastname: Nain
authors.forename: U
authors.initials: U
authors.lastname: Kaur
authors.forename: V
authors.initials: V
authors.lastname: Singh
authors.forename: V
authors.initials: V
authors.lastname: Dhawan
authors.forename: K
authors.initials: K
authors.lastname: Singh
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000328:Adult; D001241:Aspirin / Q000009:adverse effects*; D002118:Calcium / Q000032:analysis; D005260:Female; D005750:Gastric Juice / Q000737:chemistry*; D005753:Gastric Mucosa / Q000187:drug effects* / Q000502:physiology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D011188:Potassium / Q000032:analysis; D012964:Sodium / Q000032:analysis
chemical_list: D012964:Sodium; D001241:Aspirin; D011188:Potassium; D002118:Calcium